Vertical mixers are used for mixing material for agricultural and other industrial applications. Such mixers can comprise a mixer tub containing one or more vertical augers. Some augers can have blades mounted on the auger flights to help cut the material during auger rotation while the auger mixes the material.
Even with such blades, current mixers lack the ability to quickly and efficiently cut and process certain coarse materials such as biosolids, mortalities, wood, food and vegetable waste (herein after referred to as “environmental materials”). It is, therefore, desirable to provide an interference knife apparatus for use with a mixer to further aid in cutting environmental material where the knife acts in combination with the blades to provide a “scissor like” cutting action that is effective for cutting and processing the material.